Bedbug bites are usually painless but cause reactions, often pruritic, in susceptible patients.

Etiology

Bedbug infestations have become more common in the developed world in recent years. The most common bedbugs affecting humans are
Cimex lectularis (in temperate climates) and
C. hemipterus (mainly in tropical climates). Bedbugs hide in cracks and crevices of mattresses, other structures (eg, bedframes, cushions, and walls; in developing nations, mud houses and thatched roofs). They move slowly and are attracted to people by warmth and carbon dioxide. Bedbugs bite exposed skin, usually at night. A feeding is completed in 5 to 10 min.

Symptoms and Signs

Lesions are generally on exposed skin. They develop sometime between the morning after and 10 days after being bitten. Lesions can be any of the following:

Puncta only

Purpuric macules

Erythematous macules, papules, or wheals, often pruritic, each with a central hemorrhagic punctum

Bullae

Lesions may form linear patterns or may be seen in groups. Older adults develop symptoms less often than do younger people. Lesions resolve after about 1 wk. Secondary infection can develop.

Patients may be anxious about the difficulty and expense of eradicating a bedbug infestation and about the social stigma that can result from infestation. They may isolate themselves to avoid spreading infestation.

Diagnosis

Clinical evaluation

Diagnosis based on lesion appearance may be difficult because the appearance is usually nonspecific. However, most bedbug bites are larger and more edematous than other bites (eg, flea bites).

Identification of bedbugs can help confirm the diagnosis. Bedbugs have flat, oval, reddish-brown bodies. After a blood meal, the body is less flat and more reddish. Adult
C. lectularis are about 5 to 7 mm in length, and
C. hemipterus are slightly longer. Bedbug feces or blood may be evident on bed linens or behind wallpaper.

Treatment

Bedbugs should be eradicated using physical and usually chemical means. Physical means include vacuuming affected areas and laundering suspect articles, then drying them on the dryer's hottest setting. In addition, entire rooms should be treated professionally, when possible, by heating to temperatures ≥ 50° C (122° F) or with multiple insecticides.

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